DE3541138A1 - SHEET REWINDING / DISPENSING DEVICE - Google Patents

Description

VON KREISLER SCHONWALD EiSHOLD FUES FROM KREISLER KELLER SELTING WERNER

PATENT LAWYERS

Dr.-Ing. by Kreisler 11973
Dr.-Ing. KW Eishold 11981

Sharp Kabushiki Kaisha Dr-InQ-

22-22 Nagaike-cho Dr J.FFues

Abeno-ku Dipl.-Chem. Alek von Kreisler

_, Dipl.-Chem. Carola Keller

^USaKa Dipl.-Ing. G. Selting

Japan Dr. H.-K. Werner

DEICHMANNHAUS AM HAUFTBAHNHOF

D-5000 COLOGNE 1

Sg-Hi / Fe

November 19, 1985

Sheet take-up / dispenser

The invention relates to a sheet rewinder / dispenser according to the preamble of the claim 1.

Such a sheet winding / discharging device is used for automatically winding and discharging a sheet and is used, for example, in a facsimile machine, photocopier or the like. used. On the circumference of a rotating drum The sheet take-up / dispenser has two pawl members that hold a sheet between them can be. With the aid of the sheet take-up / discharge device, a sheet such as a sheet can be fed into a Film or the like wound around the rotary drum and discharged from the rotary drum.

With a known sheet take-up / dispenser it is not possible without changing the drum diameter edit a sheet that is in his

Telephone: (0221) 131041 ■ Telex: 888 2307 dopa d · Telegram: Dompatent Cologne

Linear expansion exceeds a certain value. If the sheet is longer than a specified length, if it is incorrectly wrapped around the drum, and due to the double-ply of the sheet, this can also be done will not be output properly when a sheet output signal is generated.

In addition, the known device is large in size because its mechanism is very complicated is. In JA-59 75 543 a sheet take-up / discharge device is described which has a pair on the Has claw members arranged around the circumference of the rotary drum. By opening and closing the claw links the sheet will automatically be wrapped around and ejected from the drum. With the help of this sheet-on The winding / dispensing device can provide a small device due to its very simple construction will.

However, one of the two claw members for holding the sheet has approximately the same width as that The drum and the other claw link are also wide. In addition, neither of the two claw members is elastic. Therefore, each pawl member must be very precisely attached to the drum to keep the sheet between the pawl members is held under relatively the same pressure.

Since, as shown in FIG. 1, the front face of the first claw member 5 at right angles to the peripheral surface of the Drum 2 is, as shown in Fig. 1 by dashed lines, that of the light source 7a emitted light interrupted by the front end region of the first claw member 5. Of the-

that part of sheet 1, which is immediately below of the front end region of the first claw member 5 is underexposed. This leads to disturbances when copying (copy noise) in the form that a black streak appears on the copy sheet.

The invention has for its object to provide a sheet winding / dispensing device according to the preamble of To improve claim 1 to the effect that a sheet is immediately output without being wound around the drum when its linear expansion is greater than a certain value.

This object is achieved by the sheet take-up / discharge device according to the invention solved with the features of the characterizing part of claim 1. The sheet take-up / dispenser has a rotatable one Drum around which a sheet is wound, a sheet feeding device for feeding a sheet to the drum, a sheet length detecting device for detecting the length of the sheet to be fed, one on sheet holding device disposed on the drum for holding a sheet fed to the drum and a control device for controlling the movement of the sheet holding device. the Control device controls the sheet holding device in such a way that the sheet can be moved around the drum to be wrapped, is spent when it's longer than is a certain value. The sheet winding / dispensing apparatus of the present invention is related to FIG their way of working very reliably.

In a preferred embodiment of the sheet-on Winding / dispensing device with the features of an

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Claim 2, the sheet can be securely held between two claw members which are arranged on the drum, without increased accuracy is required when attaching the claw members.
5

With the help of an advantageous embodiment of the sheet winding / dispensing device, which is characterized by the features of claim 4 is characterized, a high quality copy can be produced in a copier because copy noise is avoided by chamfering the front face of the first claw member.

Further advantageous embodiments of the invention are described in claims 3, 5, 6 and 7.
15th

An exemplary embodiment of the invention is explained in more detail below with reference to the figures.

Show it:
20th

Fig. 1 shows, on an enlarged scale, the main part of a rotary drum of a known sheet-on winding / dispenser,

Fig. 2 is a schematic representation of the sheet winding / dispensing device according to the invention,

which is used here, among other things, for feeding original documents in a copier,

Fig. 3 is a detailed perspective view of the drum of the device according to Fig. 2,
FIG. 4 shows a cross section of the drum from FIG. 3,

5a, on an enlarged scale, the front view of the second claw member,

Figs. 5b and 5c modifications of the second claw links,

6 shows, on an enlarged scale as in FIG. 1, the main part of the rotary drum of the sheet winding / dispensing device according to the invention;
FIG. 7 is a block diagram of the control circuit of FIG

Sheet rewinder / dispenser and

Fig. 8 is a flow chart showing the functions of the sheet winding / discharging device.
10

Fig. 2 is a schematic diagram of an original document feeding device of a photocopier with the sheet take-up / output device. A sheet 1 is fed between a pair of sheet feed rollers 3a, 3b, a pair of control rollers 4a, 4b and a pair of sheet guide members 10a, 10b passed through to a sheet holding area on the drum 2, which is a first Claw member 5 and a second claw member 6. The sheet 1 is in an exposure area of the Light from two light sources 7a, 7b exposed, with the front end of the sheet between the two claw members 5 and 6 is clamped so that the sheet 1 is wound around the drum 2. After the The drum has rotated several times to expose the sheet repeatedly, the sheet is locked by the second claw member 6 stripped from the drum 2 in order to pass between two sheet discharge rollers 8a, 8b via a sheet guide element 9 to be issued.

Furthermore, sheet length detection sensors S1, S2 are provided for determining the length of the sheet 1, wherein the sensor S1 in the sheet passage P and the sensor S2 between the control rollers 4a, 4b and a sheet pressure roller 11b is arranged. The distance Ll between

the two sensors S1 and S2 is set in such a way that that it is less than the length obtained by subtracting the length of the sheet output process necessary circumferential portion of the drum 2 from the circumference of the drum 2 results. In this case the Sheet discharge operation performed during the same rotation as sheet feed operation. Although it is enough that the distance Ll is smaller than the maximum circumferential length of the drum 2, assuming that the distance Ll is slightly smaller than the circumferential length described above, the sheet discharge process is carried out in the revolution period following that in which the sheet feeding operation has been carried out is.

With reference to FIGS. 3 to 5 show the structure of the sheet winding / discharging device in FIG Described in detail. The claw members 5 and 6 are respectively attached to rods 17 and 18 which are attached to the two opposite end faces 19 of the drum 2 are mounted. The first claw member 5 consists of an L-shaped bent plate which has approximately the same width as the drum 2. In contrast to the second claw member 6 according to FIG. 5a consists of a thin resilient plate, which in a blunt Angle is bent. The protruding end portion of the thin resilient plate is for holding the sheet like that Tines of a comb divided into several pieces. In addition, each of these pieces is the second claw link 6 comparatively narrow, so that the second claw member 6 has sufficient elasticity.

The drum shaft 20 for holding and rotating the drum 2 is provided with a cam 12 disposed thereon.

The cam 12 can move axially on the drum shaft 20 and does not rotate with it. A compression spring 13 presses the cam 12 against the end face 19 facing it.
5

Two cam followers 16a, 16b are like those mentioned above Rods 17 and 18 connected that upon rotation of the drum 2 in the direction of the arrow in Fig. 3 the Cam followers 16a and 16b the corresponding control surfaces of the cam 12 each touch to rotate the rods 17 and 18 through certain angles. Through the Rotation of the rods 17 and 18 opens and closes the first and second claw members 5 and 6.

For moving a movable plate 14 in the axial direction of the drum shaft 20, an actuator is in the form an electromagnet 15 is provided. By moving the plate 14, the cam 12 is displaced. Through this Mechanism, the cam 12 can be moved in the direction of the frame 21 of the sheet winding / Output device can be released from the cam follower 16a or 16b. This allows the drum 2 to the sheet 1 is wound, rotate several times without the sheet 1 being discharged from the drum 2.

In the sheet winding / discharging apparatus, the sheet 1 is fed into the sheet by the sheet feed rollers 3a and 3b Control rollers 4a and 4b out where it is stopped for a while. If the first and second Claw members 5 and 6 has moved existing sheet holding portions on the drum 2 to the position in which the protruding end of the first claw member 5 with the protruding end of the second claw member 6 a certain distance is opposite, is thereafter

- / β -

the sheet 1 in a ready state at a speed which is greater than the speed of rotation of the drum 2, again fed to between the first claw member 5 and a guide piece 24 to be pushed. The cam follower is then released 16b of the cam 12, the front end of the blade 1 by the second claw member 6 against the first Claw member 5 is pressed so that the sheet 1 is held between the claw members. Here the sheet 1 is due to the elasticity of the second claw member 6, the protruding area according to Fig. 5a is designed as the prongs of a comb, even then held securely when the opposite protruding ends of the two claw members 5 and 6 are not parallel, but slightly inclined to one another get lost. With the construction described above, the blade 1 can be between the two claw members 5 and 6 are held at relatively equal pressure to be wrapped around the drum 2, without having to increase the accuracy of the claw members 5 and 6 during installation.

According to Fig. 5b, the ends 6a of the prongs of the comb

shaped second claw member 6A loaded with rubber

layers so that the holding force for the sheet 1 is increased.

According to Fig. 5c, the width of the prongs of the second pawl member 6B and the space between adjacent ones Prongs slightly wider than the width of the prongs or the spaces between the prongs in the Figs. 5a and 5b shown modifications of the second claw member, so that an increased holding force for the Sheet 1 is achieved.

The sheet is so when the drum 2 is rotated by the light the light sources 7a and 7b exposed. The end face 5s of the protruding end of the first claw member 5 is beveled according to the angle of incidence of the light so that the light from the light source 7a, as in FIG 6, there is no penumbra in the area of the sheet 1 adjacent to the first claw member 5 generated, and this area as well as the rest of the sheet is sufficiently exposed. Even though a streak of light necessarily causing copying noise arises due to the first claw member 5, this can be avoided in the manner described with simple means and at low cost.

It should also be mentioned that the same effect that results from the beveling of the protruding face 5s of the first claw member 5 results, can also be achieved in that at least the front region of the Claw member 5 is formed from a transparent material such as resin.

In Fig. 7, a control circuit is shown, which consists of a CPU (Central Processing Unit) 22 with a a control program and similar storing ROM (Read-Only-Memory) 23 is connected, a RAM (Random Access Memory) 24, which is used as a working memory, and an interface 25. The signals from several sensors, such as the signals from the Sheet length detection sensors S1, S2 etc., given, or the interface 25 gives signals to one or more Actuators, such as on the electromagnet 15, etc.,. the end.

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Referring to the flowchart of Fig. 8, the specific functions of the sheet winding / discharging apparatus will now be described.
5

When the sheet 1 has been inserted into the device, it is checked in steps nl and n2 whether the Sheet length detection sensor Sl, which is arranged at the passage P, is active or not. If the sensor Sl is active, it is checked in step n3 whether the other sensor S2, between the control rollers 4a, 4b and the Sheet pressure roller 11b is arranged, is active or not. If the sensor S2 is active, step n4 continued. At step n4 it is checked whether both sensors S1 and S2 are active, i.e. it will checks whether both sensors S1 and S2 recognize sheet 1 or not. If both sensors Sl and S2 that Recognize sheet 1, is checked again after a certain period of time in step n5 in step n6, whether the two sensors S1 and S2 are active or not. If both sensors are still active, i.e. if both recognize the sheet 1, a sheet output signal is generated by the CPU 22 at step n7 to request a certain period of time at step n8 to activate the electromagnet 15 so that the sheet 1, which is within the same Rotation period of the drum 2 has been inserted, is output.

When the sheet 1 by means of the sheet feed rollers 3a, 3b and the control rollers 4a, 4b is supplied in the manner described above according to the states of two sensors S1 and S2 checks whether the sheet 1 is longer or shorter than the specified length. if

.at step n4 only the sensor S2 is active, a

normal operation performed. So it can be determined that a sheet 1 has been inserted that is shorter than the specified value. If both sensors S1 and S2 are active at step n4, it is determined 5 whether this condition lasts for a certain period of time or not. When the condition lasts for a certain period of time remains unchanged, the sheet 1 is immediately discharged without being wound around the drum 2. Accordingly, it can be determined that a sheet 1 has been inserted which is longer than the specified one Is worth.

With the sheet take-up / discharge device, high reliability can be achieved with a low manufacturing cost can be achieved, the manufacturing time can be significantly reduced.

Claims (6)

3541133 CLAIMS 1. Sheet take-up / discharge device with a drum for winding a sheet, a sheet feeder for feeding the sheet to the drum and a sheet holding device arranged on the drum for holding the sheet in place Sheet fed to the drum, characterized in that a sheet length detection device (Sl, S2) is provided which determines the length of the sheet fed (1), and that a control device (12,13,14,15,16a, 16b) for controlling the Movement of the sheet holding device (5,6) the sheet (1) without this around the drum (2) is wrapped around, outputs when the sheet (1) is longer than a certain value. 2. A sheet take-up / dispenser according to claim 1, characterized in that the sheet holding device (5,6) for positioning the front Edge of the sheet (1) a first claw member (5) arranged on the circumference of the drum (2) and for holding the leading edge of the sheet (1) together with the first claw member (5) as well as for Remove the leading edge of the sheet (1) wrapped around the drum (2) from the drum (2) has second claw member (6) made of elastic material and at its gripping end like the prongs of a comb is formed. 3. A sheet take-up / dispenser according to claim 2, characterized in that the gripping end of the second claw member (6) is made of soft material, e.g. rubber or the like. 4. sheet winding / dispensing device according to claim 2 or 3, characterized in that the end face (5s) of the first claw member (5) is beveled. 5. sheet winding / dispensing device according to any one of the preceding claims, characterized in, that the control device (12,13,14,15, 16a, 16b) for actuating the claw members (5,6) in Depending on the drum rotation, a cam device (12,13,16a, 16b), a movable plate (14) and one or more actuators (15). 6. sheet winding / dispensing device according to claim 5, characterized in that the actuator (15) is an electromagnet.